Pretty much as the title says. I currently own a Nexus 5, HTC One M7, iPhone 5s and just purchased a Galaxy S5 and I have to say I have never heard such an odd vibration sound as the one in the Galaxy S5. It is such a strange sound, none of my other phones have this sound at all, all of them are completely quite for the most part but the Galaxy S5 sounds like it is humming at me along with the vibration. I haven't been back to T-Mobile to compare it with other S5 phones yet so I thought I would ask on here first if anyone else was having this happen with theirs. I listen to all the main Android based podcasts Android Central included but the other day I was listening to the Pocket Now podcast and noticed that the host of the show Michael Fisher was having this issue as well yet no one else on the show knew what he was talking about. Is anyone else having this issue or is it simply not an issue at all and is completely normal for the S5 to make strange vibration sounds. Thank you in advance for any help.

Yes, I notice a slight vibration/rattling through the earpiece. I find that if I back off the volume about 20% it pretty well eliminates it. But yes, Samsung clearly could/should have done a better job designing the speaker in the earpiece.